Temperature control and supervision system for a building air conditioning system

ABSTRACT

A temperature control and supervision system for controlling and supervising the operation of a building air conditioning system having a central station and a plurality of remote stations connected by a single communication channel, wherein the control and supervision is accomplished by message transmitting and receiving apparatus at the central station and each of the remote stations for generating and interrogating serially coded messages comprising a plurality of bits in binary form.

United States Patent 1 1 Berrett et al. 1 Feb. 13, 1973 [541 TEMPERATURECONTROL AND 3,400,374 9/1968 Shumann... ...340/l72.5 SUPERVISION SYSTEMFOR A g; g f g I no son... .l BUILDING AIR CONDITIONING 3,439,329 4/1969Betz et al ..340/146.1 SYSTEM I [75] Inventors: James R. Berrett,Deerfield; Roger OTHER PUBLICATIONS J. Feulner, Mt. Prosepct, both of111. Honeywell Automation Publication, Oct, 1967.

[73] Assignee: Honeywell, Inc., Minneapolis, Minn. Primary ExaminerMeyer Perlin [22] Filed: Sept. 7, 1971 Assistant Examiner-Ronald C.Capossela Attrney-Lamont B. Koontz [21] Appl. No.: 178,095

Related U.S. Application Data [57] ABSTRACT [63] Continuation of Ser.NO. 864,679, Oct. 8, 1969, Ateinperature i f and supervl.slon System.Cox? trolling and supervising the operation of a building air abandoned.

conditioning system having a central station and a plurality of remotestations connected by a single com- [52] U.S. Cl. ..165/22, 62/140,62/180. munication channel wherein the control and Supcn/L sion 18accomplished by message transmitting and [5 Cl. t i i g apparatus atthe-central Station and each of [58'] held of Search the remote stationsfor generating and interrogating 62/412; 340/1461, 163; 235/l.l; 165/2serially coded messages comprising a plurality of bits in binary form.[56] References Cited 2 Claims, 6 Drawing Figures UNlTED STATES PATENTS3,398,889 8/1968 Bohannari 23 6/1 l 1 gag- 26 i ROOM TEMPERATURE 96 8-23I REsPoNSIvE APPARATUS I I SUPPLY Aiif i i L P" "Ei J- 9 DUCT V ,1 A

| rHEATlNG COIL I 33 FAN FLOW A "Z. 32 f H SENSOR l REMOTE Z I U TEMP.23 22 SENSOR STATIONS HOT WATER SOURCE VOLTAGE E To 800 -34 TRANSDUCER v2 W 31 6 A g 6 3 b 3| 5 GROUP #I 01- REMOTE STATIONS 1 TRANSMITTING ANDRECEIVING APPARATUS FOR SERIALLY CODED BINARY FORM MESSAGES but/J M MCOAX CABLE TRANSM SSION CHANNEL To OTHER GROUPS TRANSMITTING ANDRECEIVING APPARATUS 56 'o R E RI -\I LY E( DED INARY FORM MESSAGESCONTROL AND INDICATION APPA1;AT US.

FAN SPACE PUMP AIR DISCHARGE si:; 0Z 40 E 42 43 FLOW AIR TEMP PROCESSINGf5q 52 APPARATUS [E51 E53 PATENTEDFEIIIB IIITs 3,716,096

SHEET 10F 2 l TEMP. I 2 I SENSOR M A ROOM TEMPERATURE I VOLTAGE IRESPONSIVE APPARATUS To 800 RETURN I SUPPLY AIR DUCT; ;E E'Z I-25 u AIRDUCT FHEATING COIL 33 I FLOW 32 A f H SENSOR I Q REMOTE 2| 2 3 TEMP. w HT WATER SENSOR souRcE VOLTAGE nfgfi Q -H TO BCD w TRANSDUCER 0 (l 02 003 a 04 I 50 GROUP OF REMoTE STATIONS TRANSMITTING AND RECEIVINGAPPARATUS FOR SERIALLY CODED BINARY FORM MESSAGES LAMJLAMJ COAX CABLETRANSMISSION 1;

TO OTHER GROUPS TRANSMITTING AND RECEIVING APPARATUS 36 FOR SERIALLYCODED BINARY FORM MESSAGES CONTROL AND INDICATION APPARATus SPACE mm 43AIR DISCHARGE 21% TEMP ON FLOW AIR TEMP STATION 42 12.0 OFF 44 76.0

PROCESSING I so 52 g FEE [1U III I INVENTOR. JAMES R. BERRETT ROGER J.FEULNER A TTOR/VE).

PAIENIEDFEB 13 1975 FIG. 2

FIG. 4

FIG. 5

3,716,096 SHEET 2 BF 2 CENTRAL TO STATION 1 STATION 2 TO CENTRAL E I I II I I L I I I W TE NS UNITS TENTHS 1 CENTRAL TO STATION 3 l l l l l l ll l l l I T T STATION 62 ADDRESS PUMP ON STATION 5 TO CENTRAL l||||TI II I I I T DIGITAL OPEN INPUT SWITCH STATION TO CENTRAL I l l l l l l- II I W TENS UNITS TENTHS IN VENTOR. JAMES R. BERRETT ROGER J. FEULNERBACKGROUND OF THE INVENTION In a temperature control and supervisionsystem for controlling and supervising the operation of an air con--ditioning system in large buildings, a central station or control panelis connected to control a plurality of remote station apparatus. Thecommunication network or connections between the central station and theremote apparatus have been accomplished by the use of individualcircuits or multiplexed circuits, however, in prior art systems, thecost of installation of the communication network between the centraland remote stations has been an expensive item in the overall cost ofsuch temperature control and supervision systems.

As the cost of installation of multi-communication channels such asindividual wiring between the central station and the pluralityof'remote'stations increases, there has been an attempt to decrease suchinitial installation cost by reducing the number of wires between thecentral station and the remote apparatus.

SUMMARY OF THE INVENTION The present invention is concerned with theconnection of a central station or panel to a plurality of groups ofremote stations or apparatus in an air conditioning control andsupervision system by use of a single communication channel or coaxialcable..With the use of transmitting and receiving apparatus at thecentral station and remote stations to transmit and receive seriallycoded messages comprisinga plurality. of bits in binary form, thevarious apparatus in the building air conditioning system can beremotely controlled and remotely supervised from the central station.With this invention, the initial cost of installation is greatly reducedand even though the cost of terminal equipment at the central stationand remote stations may be somewhat greater, the overall economics, aswell as overall operation, ofthe system is greatly improved.

The present'invention is disclosed in the drawing of which: 7 I

FIG; I is a schematic representation of a central station and aplurality of remote stations containing apparatus for controlling andsupervising a building air conditioning system.

FIGS. 2, 3, 4, 5 and 6 are typical message formats used for the seriallycoded messages comprising a plurality of bits in binary form for.accomplishing the various control and supervision operations of thesystem shown in FIG. -I.

I DESCRIPTION OF THE INVENTION groups, not shown, has a similarplurality of apparatus and a panel.

A central station has a console or panel I3 which is series connected bya single transmission channel or coaxial cable 14 to panel 12 and toother similar panels 12 (not shown) associated with the other groups ofremote stations. While the apparatus of the remote stations connected topanel 12 and forming group No. 1 provide certain control and supervisionfunctions, the control and supervision function in the building airconditioning system .and the particular apparatus shown in the remotestations of group No. I has been selected as representative forexplanation purposes.

Central station panel 13 has a message transmitting and receivingapparatus 15 for sending and receiving serially coded messagescomprising a plurality of bits in binary form. A similar messagetransmitting and receiving apparatus 20 in panel 12 associated with theplurality of remote stations of group No. 1 transmits and receivesserially coded messages comprising a plurality of bits in binary form.

Specifically, the communication system between the central station andthe groups of remote stations by linking the central station panel 13with panel 12, as well as panels associated with other groups but notshown, is old in other types of systems having central and remotestations. Such communication systems connecting a central station and aplurality of remote stations are shown in the Gabrielson U.S. Pat. No.3,408,626, in the Betz et al. U.S. Pat. No. 3,439,329, in an AutomaticElectric Laboratories, Inc. publication (National TelemeteringConference-66-Paper No. BA-4.4 of May 11,1966) entitled A New Data-Gathering and Control System" by RP. Sanders, and in an InstrumentsSociety of America publication (Reprint Number 25-l-ACOS-67) entitled AComputer Oriented Supervisory Control System as Applied to a LargeProducts Pipeline by Richard T. Atwood, N.D.Rathbun and RM. Jacques. Insuch prior art communication systems, a central station is connected toa plurality of remote stations over v a communication channel forsending messages to and from the central station and remote stations ina serially coded form comprising a plurality of bits in binary form. Inthe present invention, temperature control and supervision of a buildingair conditioning system is accomplished by a serially coded message sentover a single channel transmissioncircuit or cable. During theinstallation of the control and supervision system, the central stationisco'nnected to the plurality of panels 12 and thus the 1 remotestations by means of the single coaxial cable 14 which results in a lowcost installation.

Referring to the system 10, a fan 21 circulates air from a space 11through a return and supply duct including a heating coil, 22. Fan 21isdriven by a motor 23 which is controlled by a relay 24 connected asremote station I to panel 12. The space 11 contains a room temperatureresponsive apparatus 25 comprising a temperature sensor or thermocouple26 connected to a voltage to binary code decimal transducer which isconnected to panel 12 as station 2. A pump 30 is connected to deliverhot water from a source to coil 22 when a relay 31 is energized. Therelay is connected to panel 12 as remote station 3. A flow sensor orsail switch 32 is responsive to air flow through the air duct to close aswitch connected to station 4 when a predetermined air flow exists. Thetemperature of the air being supplied to space 11 from the supply airduct is measured by a thermocouple or temperature sensor 33 connected toa voltage to binary code decimal transducer 34 associated with stationof panel 12.

The central station panel 13 has conventional control and indicatingapparatus 36 associated with the control and supervision apparatus ofthe remote stations of group No. 1 as well as the other groups. A fanstop-start switch 40 is used for controlling the operation of relay 24of remote station 1, a digital read-out space temperature indicator 41is associated with the temperature responsive apparatus 24 of remotestation 2, a pump control switch 42 is for controlling the pump relay 31associated with station 3, an indicator light 43 is associated with theflow sensor of station 4, and a digital read-out temperature indicator44 indicates the discharge air temperature of temperature sensor 33associated with remote station 5.

The central station panel 13 has processing apparatus 45 of aconventional type for accomplishing the control and supervision of thecontrol and indicating apparatus by sending serially coded messages inbinary form, utilizing message transmitting and receiving apparatus 15,over the single series communication channel to the various panels suchas panel 12 of group No.

1 to accomplish the control and supervision of building air conditioningsystem 10. Processing apparatus 45 comprises a digital input push buttonpanel 50 for selecting various control and supervision functions and forexecuting control commands with the execute button 51 or supervisingapparatus with a scanning operation accomplished by a scan button 52.Processing apparatus 45 translates the various inputs into messageswhich are serially transmitted over the single communication channel 14to the remote panels 12. i

For explanation purposes, typical message formats for various operationsassociated with the building air conditioning system and the specificapparatus shown with remote stations 1 to 5 of group No. 1 are shown inFIGS. 2 to 6. FIG. 2 is a 12 bit message which is transmitted from thecentral station to the remote groups and by means of the station addressmade up of 6 bits, station 1 of group No. l is selected and by means ofa specific, bit 61, a motor start operation is accomplished by theenergization of relay 24, shown in FIG. 1. Specifically, the operationis accomplished by addressing the. station by the push button input50 ofprocessing apparatus 45 of central station panel 13 and executing a fanon operation with the fan switch 40 when execute button 51 is operated.The message transmitting apparatus sends out the serially coded messageof FIG. 2 to be received by the message receiving apparatus of panel 12.

When the central station is in a scan operation as accomplished, by.button 52, various functions associated with the remote stations of.panel 2 are reported at the central station. By means of an input frompanel 12 to the'central station, as shown in FIG. 3, a 12 bit word madeup of three groups of 4"bits to provide a digital outputfrom thetemperature responsive apparatus which would be identified andinterpreted as the space temperature 72 F at indicator 4].

The energization of pump is accomplished by the operation of push buttoninput 50 of processing apparatus 45 to address the station 3 of groupNo. l by a station address such as shown at 62 in FIG. 4 with a singlebit 63 used to energize relay 31 to turn the pump on.

The scanning operation accomplished by the operation of the scan button52 of the central station supervises the flow of air at remote station 4to report the condition of the flow sensor switch by a message such asshown in FIG. 5 in which bit 64 indicates a digital ing three portionsfor reporting the temperature as 78 F at the discharge of the airconditioning system 10.

OPERATION OF THE INVENTION With a central station or panel 13 located ina building and connected by means of a single transmission channel orcoaxial cable 14 to a plurality'of panels such as 12 representing groupsof remote stations, serially coded messages comprising a plurality ofbits in binary form are transmitted from the central station to theremote groups of remote stations and from the groups of remote stationsto the central panel to accomplish the various control and supervisionoperations of the building air conditioning control and supervisionsystem. The single communication channel is connected in a series mannerbetween the various panels such as 12 associated with a plurality ofgroups of remote stations. From the central station,- the operator cancontrol and supervise the building air conditioning system by eithersending serially coded messages over the single transmission channel toselectively control various functions of the remote stations or receivefrom tion of the building air conditioning system at the centralstation.

The embodiments of the invention in which an exclusive'property or rightis claimed are defined as follows:

1. In a temperature control and supervision system for controlling andsupervising the operation of building air conditioning system whereinthe physical location of the apparatus of the system is separated suchgreat distances that the use of indi-vidual cha'nnels of communicationbetween each of the various apparatus to accomplish indication andcontrol would be complex and expensive comprising:

a central station comprising;

air conditioning temperature indicating apparatus for use by an operatorto observe the temperature of selected apparatus of a building airconditioning system, 1 air conditioning control apparatus to controlselected apparatus of said building air conditioning system, messagetransmitting and receiving apparatus to transmit and receive seriallycoded messages comprising a plurality of bits in binary form for abinary code decimal message format, and means connecting said airconditioning temperature indicating apparatus and said air conditioningcontrol apparatus to said message transmitting and receiving apparatusincluding means for receiving messages in binary code decimal formatforproviding output signals indicative of temperatures for said airconditioning temperature indicating apparatus and including means forsending messages in binary code decimal format upon receiving signalsfrom said air conditioning control apparatus for controlling remoteapparatus of said air conditioning system,

a plurality of groups of remote stations each comprising;

second message transmitting and receiving apparatus to transmit and toreceive serially coded messages comprising a plurality of bits in binaryform for a binary code decimal message format,

air conditioning temperature sensing means for sensing the temperatureof apparatus of said air conditioning system to provide an output signalindicative of the temperature,

air conditioning control means for controlling apparatus of said airconditioning system upon receiving control signals indicative of thechange to be accomplished, and

means connecting said temperature sensing means and said control meansto said second message transmitting and receiving apparatus includingmeans for providing messages in binary code decimal format indicative oftemperature upon receiving said output signal of said air conditioningtemperature sensing means, and including means upon receiving messagesin binary code decimal format indicative of a change to be accomplishedfor providing control signals to said air conditioning control means,and

a single channel transmission means series connecting said messagetransmitting and receiving apparatus of said central station to each ofsaid second message transmitting and receiving apparatus of saidplurality of groups of remote stations whereby serially coded messageshaving a plurality of bits for a binary code decimal format are sent toand from said central station and said groups of remote stations so thatthe temperature of said temperature sensing means at any one of saidplurality of remote stations can be indicated at said temperatureindicating apparatus of said central station and said control means atone of said plurality of remote stations can be controlled by saidcontrol apparatus of said central station.

2. The invention of claim 1 wherein, said remote stations are locatedthroughout a building, said stations include a fan motor control means,a water pump control means, an air flow sensing means, and a temperaturesensing means, and

said transmission means comprises a coaxial cable to provide said singlechannel connection to be used throughout the building from said centralstation whereby a fan motor is adapted to be controlled through said fanmotor control means, a water pump is adapted to be controlled throughsaid water pump control means, the flow of air is adapted to becontrolled through said water pump control means, the flow of air isadapted to be indicated by said air flow sensing means and thetemperature of the air is adapted to be indicated by said temperatursensing n ear s.

1. In a temperature control and supervision system for controlling andsupervising the operation of building air conditioning system whereinthe physical location of the apparatus of the system is separated suchgreat distances that the use of individual channels of communicationbetween each of the various apparatus to accomplish indication andcontrol would be complex and expensive comprising: a central stationcomprising; air conditioning temperature indicating apparatus for use byan operator to observe the temperature of selected apparatus of abuilding air conditioning system, air conditioning control apparatus tocontrol selected apparatus of said building air conditioning system,message transmitting and receiving apparatus to transmit and receiveserially coded messages comprising a plurality of bits in binary formfor a binary code decimal message format, and means connecting said airconditioning temperature indicating apparatus and said air conditioningcontrol apparatus to said message transmitting and receiving apparatusincluding means for receiving messages in binary code decimal format forproviding output signals indicative of temperatures for said airconditioning temperature indicating apparatus and including means forsending messages in binary code decimal format upon receiving signalsfrom said air conditioning control apparatus for controlling remoteapparatus of said air conditioning system, a plurality of groups ofremote stations each comprising; second message transmitting andreceiving apparatus to transmit and to receive serially coded messagescomprising a plurality of bits in binary form for a binary code decimalmessage format, air conditioning temperature sensing means for sensingthe temperature of apparatus of said air conditioning system to providean output signal indicative of the temperature, air conditioning controlmeans for controlling apparatus of said air conditioning system uponreceiving control signals indicative of the change to be accomplished,and means connecting said temperature sensing means and said controlmeans to said second message transmitting and receiving apparatusincluding means for providing messages in binary code decimal formatindicative of temperature upon receiving said output signal of said airconditioning temperature sensing means, and including means uponreceiving messages in binary code decimal format indicative of a changeto be accomplished for providing control signals to said airconditioning control means, and a single channel transmission meansseries connecting said message transmitting and receiving apParatus ofsaid central station to each of said second message transmitting andreceiving apparatus of said plurality of groups of remote stationswhereby serially coded messages having a plurality of bits for a binarycode decimal format are sent to and from said central station and saidgroups of remote stations so that the temperature of said temperaturesensing means at any one of said plurality of remote stations can beindicated at said temperature indicating apparatus of said centralstation and said control means at one of said plurality of remotestations can be controlled by said control apparatus of said centralstation.
 1. In a temperature control and supervision system forcontrolling and supervising the operation of building air conditioningsystem wherein the physical location of the apparatus of the system isseparated such great distances that the use of individual channels ofcommunication between each of the various apparatus to accomplishindication and control would be complex and expensive comprising: acentral station comprising; air conditioning temperature indicatingapparatus for use by an operator to observe the temperature of selectedapparatus of a building air conditioning system, air conditioningcontrol apparatus to control selected apparatus of said building airconditioning system, message transmitting and receiving apparatus totransmit and receive serially coded messages comprising a plurality ofbits in binary form for a binary code decimal message format, and meansconnecting said air conditioning temperature indicating apparatus andsaid air conditioning control apparatus to said message transmitting andreceiving apparatus including means for receiving messages in binarycode decimal format for providing output signals indicative oftemperatures for said air conditioning temperature indicating apparatusand including means for sending messages in binary code decimal formatupon receiving signals from said air conditioning control apparatus forcontrolling remote apparatus of said air conditioning system, aplurality of groups of remote stations each comprising; second messagetransmitting and receiving apparatus to transmit and to receive seriallycoded messages comprising a plurality of bits in binary form for abinary code decimal message format, air conditioning temperature sensingmeans for sensing the temperature of apparatus of said air conditioningsystem to provide an output signal indicative of the temperature, airconditioning control means for controlling apparatus of said airconditioning system upon receiving control signals indicative of thechange to be accomplished, and means connecting said temperature sensingmeans and said control means to said second message transmitting andreceiving apparatus including means for providing messages in binarycode decimal format indicative of temperature upon receiving said outputsignal of said air conditioning temperature sensing means, and includingmeans upon receiving messages in binary code decimal format indicativeof a change to be accomplished for providing control signals to said airconditioning control means, and a single channel transmission meansseries connecting said message transmitting and receiving apParatus ofsaid central station to each of said second message transmitting andreceiving apparatus of said plurality of groups of remote stationswhereby serially coded messages having a plurality of bits for a binarycode decimal format are sent to and from said central station and saidgroups of remote stations so that the temperature of said temperaturesensing means at any one of said plurality of remote stations can beindicated at said temperature indicating apparatus of said centralstation and said control means at one of said plurality of remotestations can be controlled by said control apparatus of said centralstation.